In 3 Nephi 15, the Lord announces that the Law of Moses has been fulfilled in Him. He has accomplished all its requirements, and its performances in large part are done away.
The law of Moses was a behavioral discipline. But we know that, as President Packer said, the gospel of Jesus Christ has greater power to change behavior than even a study of behavior itself does.
I believe this is because the gospel is a study in conviction. Our strength, our drive, everything we believe and feel and do can be affected by a testimony of the gospel. Why? Because we grow to love the Lord. We grow to see and understand that He loves us.
As we live our lives, we are given many chances to develop deep convictions about everything from religion to personal interests like our hobbies. But as members of Christ’s church, we need to recognize that these things aren’t mutually exclusive; developing our talents, loving the skills the Lord Himself has given us enough to work at them, having the conviction to build up a gift even when it may at first seem trivial— all these things are part of our Father’s grand design.
When we say we can make music or art or that we can teach or perform as an athlete “for the glory of God”, that is not just a way to justify devoting time to a hobby. If we can be dedicated day by day to the note-upon-note practice of a musical instrument, loving every morsel of progress we make, then we can surely see the power of daily devotion to Christ and His line-upon-line gospel.
I pray that in all ways, we can be wholly invested in the Lord. I know that He spends each moment of His eternity so invested in us, and that every good thing—even those things that at first seem small—are borne of Him.